VOLTAMMETRY OF CAPTOPRIL ON THE HANGING MERCURY DROP ELECTRODE

The electrochemical behavior of 1-[(2S)-3-mercapto-2-methyl-1-oxopropyl]-L-Proline (Captopril) was studied by cyclic voltammetry (CV). The influence of pH on the diffusion waves and the parameters associated with them were studied. The diffusion waves exhibit a quasi-reversible mechanism at low pH (under pH = 6.5) and an irreversible electron transfer at higher pH values. Product adsorption waves (prepeaks) showing marked reversible behavior were observed and studied only at a pH of 2.20. Various parameters such as electron transfer rate (K(sh)), maximum surface excess concentration (GAMMA-t), electron transfer coefficient (alpha), Frumkin's interaction parameter, (g) and diffusion coefficient (D(r)) were calculated.